Which vitamin deficiency is most commonly associated with obstructive jaundice?

Obstructive jaundice occurs when there is a blockage in the bile duct system, leading to increased levels of bilirubin in the blood. This condition can affect the absorption of fat-soluble vitamins, particularly vitamin K, which is crucial for the synthesis of clotting factors in the liver.

Vitamin K is particularly important because it plays a critical role in the production of prothrombin and other clotting factors. When obstructive jaundice is present, the absorption of dietary fats and fat-soluble vitamins, including vitamin K, is impaired. This can lead to a deficiency that may manifest as coagulopathy, characterized by an increased risk of bleeding due to inadequate clot formation.

In contrast, the other vitamins listed – D, B12, and C – are either water-soluble or their deficiency is not typically associated with obstructive jaundice. Vitamin D is essential for calcium metabolism, vitamin B12 is crucial for red blood cell formation and neurological function, and vitamin C acts primarily as an antioxidant and in collagen synthesis. However, they do not have the same direct connection to the effects of obstructive jaundice on the body's ability to absorb fat-soluble vitamins, which makes vitamin K the most relevant in this context.